Apple sensibly stipulate minimum requirements to preserve an adequate user experience. Adobe allow their program to run on anything, but what of the user experience? As with everything, "minimum requirements" is a subjective thing, and will vary from user to user. Both programs are aimed squarely at "professional level users" and thus, I don't mark aperture down for having greater stipulated requirements. Both benefit from as fast, large and meaty a computer as possible.

One should judge the applications on functionality. Compare their speed, but don't compare minimum requirements.

For your home machines, use iPhoto, iView Media Pro, or some other program.